<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>402 Payment Required</title>
</head><body>
<h1>Payment Required</h1>
<p>The server encountered an internal error or
misconfiguration and was unable to complete
your request.</p>
<p>Please contact the server administrator at
www@virtualbox.org to inform them of the time this error occurred,
and the actions you performed just before this error.</p>
<p>More information about this error may be available
in the server error log.</p>
</body></html>
It could be a combination of IP + user agent (+ something else) that's causing me trouble.